Pulse oximeters are well known and accepted for use in clinical environments. Pulse oximeters measure the relative percentage of oxygen carrying hemoglobin molecules in the blood. This measurement is commonly referred to as oxygen saturation or SpO2. Pulse oximeters generally shine light of predetermined wavelengths at a measurement site on the patient and measure the attenuation of the light by the tissue using a detector. Some Pulse oximeters also include additional capabilities to measure other blood analyte levels in addition to oxygen saturation. Non-invasive measurement devices capable of measuring multiple physiological parameters, including oxygen saturation, methemoglobin levels and carboxyhemoglobin levels, are available from Masimo Corporation of Irvine Calif.